vsc7939 Vitesse Semiconductor Corp, vsc7939 Datasheet
vsc7939
Related parts for vsc7939
vsc7939 Summary of contents
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... Supply Current of 33mA at 3.3V General Description The VSC7939 is a single 3. supply laser diode driver specially designed for SONET/SDH applica- tions up to 3.125Gb/s. External resistors set a wide range of bias and modulation currents for driving the laser. Data and clock inputs accept differential PECL signals. The automatic power control (APC) loop maintains a constant average optical power over temperature and lifetime ...
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... Typ Max TBD 45 1 100 100 230 900 ±15 1.5 18 1000 -480 -50 480 90 - 200 Internet: www.vitesse.com Preliminary Data Sheet VSC7939 Units Conditions ps LATCH=high ps LATCH=high ns ps 20% to 80% ps 20% to 80% ps See Notes 1, 2 bits Jitter BW=12kHz to 20MHz, ps p-p 0-1 pattern. Units Conditions R =7.3k MODSET R =4 ...
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... Preliminary Data Sheet VSC7939 Symbol Parameter Modulation Current Absolute Accuracy Modulation Current Stability A BIASMON to I Gain BIAS BIAS A MODMON to I Gain MOD MON NOTES: (1) Both I and I will turn off if any of the current set pins are grounded. (2) Assumes laser diode to monitor diode transfer func- ...
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... VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com VITESSE SEMICONDUCTOR CORPORATION (1) = +85°C, TQFP derate 20.8mW/°C above +85°C) .......................1350mW A )................................................................................................. -40°C to +85°C A Internet: www.vitesse.com Preliminary Data Sheet VSC7939 + 0.5V 1.5V 0.5V) CC G52350-0, Rev 3.2 02/26/01 ...
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... Laser Diode Driver with Automatic Power Control Figure 1: Pad Assignments 1773µm (0.0698") Pad 9 Pad 8 Pad 7 Pad 6 Pad 5 CLK+ VCC1 GND1 VCC1 DATA- (Pin 5) (Pin 4) (Pin 3) VSC7939 (Pin 19) (Pin 20) (Pin 21) Pad 28 Pad 29 Pad 30 Pad 31 Pad 32 DB_OUT+ OUT+ OUT- DB_OUT- VCC4 1773µm x 2233µm (0.0698" x 0.0879") 625 " ...
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... GND3 159.45 1058.475 RESERVED 159.45 943.475 APCSET 159.45 828.475 GND2 159.45 713.475 MODSET 159.45 598.475 BIASMAX 159.45 483.475 VCC2 Internet: www.vitesse.com Preliminary Data Sheet VSC7939 Coordinates (µm) Pad No (Pin 17) 159.45 368.475 26 369.525 159.45 27 (Pin 18) 484.525 159.45 28 599.525 159.45 29 (Pin 19) 714 ...
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... VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 G52350-0, Rev 3.2 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com 02/26/01 VITESSE SEMICONDUCTOR CORPORATION Laser Diode Driver with Automatic Power Control Figure 2: Pin Diagram VSC7939 Internet: www.vitesse.com SONET/SDH 3.125Gb GND 22 ...
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... Connect resistor to GND to set desired modulation current. Connect resistor to GND to set maximum bias current. The APC function can subtract from this value, but cannot add to it. Internet: www.vitesse.com Preliminary Data Sheet VSC7939 if LATCH function is not used. CC for data retiming and GND for direct data. for CC flows when input data is high ...
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... VSC7939 Detailed Description The VSC7939 is a high-speed laser driver with Automatic Power Control. The device is designed to operate up to 3.125Gb/s with a 3. supply. The data and clock inputs support PECL inputs as well as other inputs that meet the common-mode voltage and differential voltage swing specifications. The differential pair output stage is capable of sinking up to 60mA from the laser with typical rise and fall times of 60ps ...
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... Laser Diode Driver with Automatic Power Control Modulation and Bias Current Monitors The VSC7939 provides monitoring of the modulation and bias currents vias BIASMON and MODMON. These pins sink a current proportional to the actual modulation and bias currents. MODMON sinks approxi- mately 1/28th of the amount of modulation current and BIASMON sink approximately 1/35th of the amount of the bias current ...
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... Therefore, the inductor L P Input/Output Considerations Although the VSC7939 is PECL-compatible, this is not required to drive the device. The inputs must only meet the common-mode voltage and differential voltage swing specifications. Power Consumption The following equation provides the device supply current (I ...
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... Page 12 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com VITESSE SEMICONDUCTOR CORPORATION MODSET = 3.3V BIASMAX = 3.3V Internet: www.vitesse.com Preliminary Data Sheet VSC7939 I vs. R MODSET MODSET vs. R BIASMAX ...
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... Preliminary Data Sheet VSC7939 I vs APCSET Rise and Fall Times T=8 C, V=3.3V © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 G52350-0, Rev 3.2 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com 02/26/01 VITESSE SEMICONDUCTOR CORPORATION Laser Diode Driver with Automatic Power Control , = 3 ...
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... SONET/SDH 3.125Gb/s Laser Diode Driver with Automatic Power Control Applications Information The following is a typical design example for the VSC7939 assuming 3.3V operation with APC. Select a Laser The Table 7 provides specifications for a typical communication-grade laser capable of operating at 2.5Gb/s. Table 6: Typical Laser Characteristics ...
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... Preliminary Data Sheet VSC7939 Standard values for these values are R MODMON would indicate a modulation current of: Wire Bonding For best performance, gold ball-bonding techniques are recommended. Wedge bonding is not recom- mended. For best performance and to minimize inductance keep wire bond lengths short. ...
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... Controlling dimension: millimeter 3. This outline conforms to JEDEC Publication 95 Registration MS-026 Page 16 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com VITESSE SEMICONDUCTOR CORPORATION Internet: www.vitesse.com Preliminary Data Sheet VSC7939 G52350-0, Rev 3.2 02/26/01 ...
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... VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 G52350-0, Rev 3.2 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com 02/26/01 VITESSE SEMICONDUCTOR CORPORATION Laser Diode Driver with Automatic Power Control xx VSC7939 Internet: www.vitesse.com SONET/SDH 3.125Gb/s Package RP: 32-Pin TQFP W: Dice Waffle Pack Page 17 ...
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... SONET/SDH 3.125Gb/s Laser Diode Driver with Automatic Power Control Page 18 © VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012 Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com VITESSE SEMICONDUCTOR CORPORATION Internet: www.vitesse.com Preliminary Data Sheet VSC7939 G52350-0, Rev 3.2 02/26/01 ...